1. Field of the Invention
Embodiments of the invention are related to setting a packer assembly in a wellbore in a single trip into a wellbore. Embodiments of the invention are also related to retrieving the packer assembly from the wellbore using a retrieval tool in a single trip into the wellbore. Embodiments of the invention are further related to releasing the retrieval tool from the packer assembly while in the wellbore during a retrieval process in the event that the packer assembly will not release from the wellbore or otherwise becomes wedged in the wellbore and is prevented from removal.
2. Description of the Related Art
A packer assembly, such as a straddle system, has typically been used to isolate an area of interest in a wellbore formation to conduct various downhole operations, such as fracturing operations or other wellbore treatment operations. In one example, the packer assembly is located adjacent the area of interest, an upper packer is actuated into sealing engagement with the surrounding wellbore above the area of interest, and then a lower packer is actuated into sealing engagement with the surrounding wellbore below the area of interest, thereby “straddling” the area of interest. In another example, the packer assembly may include only one packer that is used to isolate the area of interest in the formation. A downhole operation may be conducted with the isolated formation.
The entire packer assembly, however, is located in the wellbore in multiple sections, requiring (costly and time consuming) multiple trips into the wellbore. For example, the lower packer may be located in the wellbore in one trip, and then the upper packer may be located in the wellbore in a second subsequent trip. Some packer assemblies may be lowered into a wellbore in a single trip, but these packer assemblies require concentric mandrel configurations to operate the upper and lower packers downhole. Such concentric mandrel configurations prevent the use of other fluid flow devices, such as a sliding sleeve, a safety valve, a side pocket mandrel, etc., between the upper and lower packers that may be utilized in certain downhole operations, limiting the flexibility of the packer assembly.
Retrieving the packer assemblies described above has also proven difficult. A retrieval tool is generally lowered into the wellbore and attached to the packer assembly to release and retrieve the packer assembly from the wellbore. Multiple trips into the wellbore may be necessary to remove the entire packer assembly from the wellbore. During the retrieval process, sometimes the packer assembly will not release from the wellbore or becomes jammed in the wellbore as it is being removed. In such situations, since the retrieval tool is generally incapable of releasing from the packer assembly, both the retrieval tool and the packer assembly require subsequent emergency recovery trips into the wellbore.
Therefore, there is a need for a packer assembly that can be located in and retrieved from a wellbore in a minimal number of trips into the wellbore. Therefore, there is also a packer assembly that can be integrated with other flow devices to enhance the flexibility of the assembly. There is a further need for a retrieval tool that can release from a packer assembly during a retrieval process in the event that the packer assembly is prevented from removal from the wellbore.